Non-Small Cell Carcinoma of the Lung with Rib Destruction and Possible Cavitation

Non-Small Cell Carcinoma of the Lung

The patient complained of feeling "something snap" in her chest, corresponding to the

pathological fractures seen radiographically. CT scan of the head with contrast revealed enhancing mass lesions surrounded by edema.

1. "Bronchogenic" carcinoma includes:
   • Squamous cell (30-50% of cases -- highest correlation with smoking).
   • AdenoCA (35% of cases -- most prevalent form on U.S.).
     • Bronchoalveolar is subtype (?10% of cases).
   • Large cell anaplastic (10-15% of cases).
   • Small ("oat") cell (20-30% of cases -- considered Stage IV at presentation.
     • Hence the important distinction between small cell and non-small cell, as in this case.
     • Often associated with endocrinopathies b/o secretion of hormone-like substances.
   • Rare varieties -- clear cell carcinoma, carcinosarcoma, basal cell carcinoma of the bronchus.
   
   
   
2. Interesting points about Lung CA in general:
   • Usually solitary but can predispose to a second primary.
   • Doubling time between 1 and 18 months, depending on subtype.
   • Dystrophic calcification in 6 to 7%.
   • Screening programs have not shown to be effective.
     • 15-20% of patients with lung CA can have malignant cells in the sputum and a normal chest x-ray.
     • Nodules may be missed in screening studies even of high risk patients.
   
   
   
3. Interesting points about Lung Ca subtypes:
   • AdenoCA:
     • Usually peripheral and often forms in scars or in lungs with interstitial disease (e.g., Rheumatoid Lung).
     • May, itself, induce fibrotic (desmoplastic) changes.
     • Usually associated with hilar and mediastinal node involvement.
     • Patients often asymptomatic but distant metastases (e.g., brain, adrenal) may be present at the time of diagnosis.
   • Squamous cell CA:
     • Often central, slow growing, with late metastasis.
     • Atelectasis and post-obstructive pneumonia are common.
       • May therefore be discovered as the reason for persistent or recurring atelectasis or infiltrate.
     • Most likely tumor subtype to cavitate.
   • Bronchoalveolar CA:
     • A subtype of AdenoCA.
     • Can present as solitary nodule, multiple nodules.
     • Best know for appearing as infiltrate(S) with air-bronchograms, thus simulating pneumonia.
     • The most indolent subtype.
   
   
   
4. Staging Lung CA is difficult but crucial:
   • Uses standard T,N,M classification of tumor.
   • Determines resectability and survivability.
   • Basically, the worse the prognosis:
     • The larger the tumor.
     • The more central.
     • Involvement of hilar and mediastinal nodes and structures.
     • Pleural fluid (even if not containing malignant cells!).
   • Distant mets, malignant pleural fluid is the worst.
   • CT used for staging but frequently over- and under- estimate the Stage.
     • Bronchoscopy useful for diagnosis.
     • MRI useful for "problem solving."